Almost half of adults with food allergies say they developed them during adulthood, according to a new study from the American College of Allergy, Asthma and Immunology (ACAAI).

“Food allergies are often seen as a condition that begins in childhood, so the idea that 45 percent of adults with food allergies develop them in adulthood is surprising,” said Ruchi Gupta, MD, MPH, ACAAI member and lead author of the study, in a statement. “We also saw that, as with children, the incidence of food allergies in adults is rising across all ethnic groups.”

The most common food allergy among adults is shellfish, affecting an estimated 3.6 percent of U.S. adults. This marks a 44 percent increase from the 2.5 percent prevalence rate published in an influential 2004 study. New data also suggests that adult tree nut allergy prevalence has risen to 1.8 percent from a 2008 estimate of 0.5 percent, an increase of 260 percent.

“Our research also found that, among black, Asian and Hispanic adults, the risk of developing a food allergy to certain foods is higher than for whites, specifically for shellfish and peanuts,” said food allergy researcher Christopher Warren, PhD candidate and study co-author. “For example, Asian adults were 2.1 times more likely to report a shellfish allergy than white adults, and Hispanic adults reported a peanut allergy at 2.3 times the frequency of white adults. Because many adults believe food allergies mostly affect children, they may not think to get tested. It is important to see an allergist for testing and diagnosis if you are having a reaction to a food and suspect a food allergy.”

People may not recognize they have a food allergy, and believe their reaction is a food intolerance. They might not seek the help of an allergist for diagnosis, but allergists are specially trained to administer allergy testing and diagnose the results. Allergists can tailor a plan specific to your allergies.